Baffle construction for air valves



Jan. 17,1939. H. B. AHLBERG 2,144,097

BAFFLE CONSTRUCTION FOR AIR VALVES Filed June 16, 1937 Fig.1.v 14 fPatented Jan. 17, 1939 UNITED STATES PATENT OFFICE 2,144,097 RAFFLECONSTRUCTION FOR Am VALVES Application June 16, 1937, Serial No. 148,542

7 Claims.

This invention pertains to air valves of the type commonly used forventing air from steam radiators used in heating systems.

Steam heating systems are usually either the sc-called one-pipe systemor the two-pipe system. In either case it is necessary that there be avent on the radiator so that the entrapped air may have some means ofescape ahead of the on-coming steam. Valves are, therefore, providedwhich permit the escape of air until such time as steam reaches thevalve whereupon the temperature is raised to a predetermined point andthe valve automatically closes.

Obviously, as steam reaches a cold radiator rom the steam main or riser,condensation takes place rapidly, but as the radiator is graduallywarmed, this condensation diminishes. However, there will always be acertain amount of condensate present in the escaping air as the steamand air are inevitably mixed.

As the air escapes from the radiator it carries with it some condensatein the form of finely divided particles of water. This, however, is notobjectionable for the water promptly evaporates into the atmosphere ofthe room. It so happens, however, that due to the construction of theair venting valves that are in common use, water will gradually becollected therein from the saturated air passing therethrough.Ordinarily this condensate will drain back into the radiator from theair venting valve, but on occasion the air rushing from the radiatorinto the valve will pick up the condensate in such a way that it will becarried in a body as a slug of water to the vent ,oi the valve,whereupon it is shot forcibly out of the valve to the damage of thefloor and wall and sometimes even the ceiling of the room. Action ofthis type is called spitting and is considered objectionable by theusers.

Various means have been proposed for 0vercoming the spitting tendency ofvalves, but as far as I am aware no really satisfactory means has beenput in use as yet. Spitting is still common in both types of valves nowin general use, that is, in the non-vacuum and vacuum types. Myinvention proposes a means whereby spitting is entirely overcome in boththe aforementioned types of valves. My construction is easy to make andlow in cost and may be used with any type f valve employing athermostatic float or even an ordinary float which does not operateunder the influence of heat.

Other objects and accomplishments of my invention will become apparentas the description proceeds with the aid of the accompanying drawing, inwhich;

Fig. 1 is a cross section of a typical vacuum type air valve, certain ofthe parts being shown in elevation;

Fig. 2 is a vertical section on the line 2--2 of Fig. 1 showing apreferred form of my baliie;

Figs. 3, 4, and 5 are views similar to Fig. 2 but showing modified formsof baffies.

Referring to Fig. 1, the vacuum valve which I have selected as beingtypical of current practice and in which I have incorporated mynonspitting mechanism comprises a base 2 having an externally threadednipple 4 attached for connection with a radiator. A casing 6 has aflange 8 which rests on a gasket Ill mounted on base 2. These parts areall drawn together by the nut i2. 7

The upper end of casing 6 is provided with a port it terminating at itsinner end in a valve seat iii. Centrally located in the base is an ad--justing mechanism l8 which is used in varrying the effective ventingarea of the valve, but as it is not a part of this invention there is noneed for describing it in detail. The adjusting mechanism i8 carries ahollow stem 26 on which is mounted a bellows 22.

The bellows, in turn, supports a thermostatic float 24 which has on itsupper end a valve pin 26 positioned to engage valve seat It. As thebellows 22 is rigidly connected with stem 2% no lateral support for thebellows is needed. On the other hand, however, the thermostatic float 24must be guided in such a way that valve pin 26 will be centered withrespect to port it.

I provide guide means at the lower portion of float 24 in the form of acombination guide and water bafile 28 which in plan view may take theform shown in Figs. 2, 3, 4, and 5. It will be noticed that there is asmall clearance 36 between the inner circumference of the baffle and thefloat which it is intended to guide. This clearance is ample to permitthe passage of water saturated air. Additional passages 32 are alsoprovided in the baffle for a purpose that will be apparent presently.

For ease in installing bafile 28 within casing 6, I have provided thethree upturned legs 29, integral with the baffle 28 and which arearranged by virtue of the set originally given them to press outwardlyagainst the inside of the casing. Thus there is ample frictionalengagement between the legs and the casing to hold the baffle firmly inposition. Other attaching objection.

means could, of course, be used. For example, the baffle could besoldered in place.

Heretofore in valves of the type shown it has been customary to provideguide mechanism for the float either in the form of ribs extendinginwardly from the wall of the casing or in the form of a strip of metalor wire positioned circumferentially within the casing but bent in sucha way as to guide the float. When such means for guiding a float areused water which has accumulated at the bottom of base 2 as at 34 couldbe driven upwardly as a slug of water by on-coming air, past the float,and out the port M. Thus the type of guide just described in no wayprevented spitting.

Another form of guide that has been used provided an imperforate annularring mounted within the casing about the lower part of the float leavingbut small clearance between the ring and the float. This type of guideis adequate to prevent spitting but it has the following serious The airescaping from the valve is saturated with water vapor, some of whichcondenses in the upper portion of the valve and collects on the upperside of the annular guide ring. The space between the guide ring andfloat, however, is so limited, if the guide ring is to perform properlyits function as a guide, that the surface tension and capillary actionof the water prevents its downward passage between the guide and float.Thus, in time, a considerable amount of water will accumulate above theguide ring and the valve will reach a condition commonly known aswaterlogged, in which state proper functioning is prevented.

By my construction, however, I provide a combination bafiie and guidemeans which permits passage of Water saturated air and at the same timeis of sufficient area to efiectively check any slugs of water that mightbe driven upwardly toward port Hi. The passages 32 are of such size thatsurface tension or capillary action will not be effective to prevent anycondensate which may collect on the upper side of baffie 23 from readilyrunning downwardly therethrough to re-collect in base 2 from which itmay be drained back to the radiator through syphon tube 35.

While I have shown certain preferred forms of passages 32 which areadequate to cause breaking of the surface tension of the water, I wishit to be distinctly understood that other forms of openings may be used.A requisite of my invention is that the baffle in acting as a guide mustfit the float 2t closely enongh so as to keep it in satisfactoryalignment but at the same time there must be no binding whatsoeverbetween the guide and float, Another requisite is that the passage 32must be adequate to permit the return of any condensate that may collecton top of the bafiie but at the same time the passages must be smallenough and so distributed that a slug of water, driven from the base 2toward port M, will be checked or broken up so that spitting will nottake place. To effectively check spitting it is necessary that the waterbe delayed or diffused so that the air which is driving the water mayget by and reach the port It first. This result, my combination baffleand guide eflectively accomplishes.

While I have described my invention by reference to a preferred form Iwish it to be distinctly understood that I do not intend to be limitedthereby but only by the appended claims.

I claim:

1. In an air valve for steam radiators, in combination, a casing havingan intake port and a vent, vent closing means comprising a float havinga valve pin mounted thereon, and a guide means for said float, saidguide means comprising an annular baffle positioned circumferentiallywithin said casing and surrounding said float with slight clearancetherebetween, said clearance being insuflicient to permit free downwardpassage of water that may accumulate above said baflie, said baiilebeing cut away at a selected area to provide an opening large enough topermit free downward flow of water that may accumulate above saidbattle, and resilient means for holding said baffie in place byfrictional engagement with said casing.

2. In an air valve for use on steam radiators, in combination, a casinghaving an inlet and a vent, means for closing said vent including afloat, a guide for said float in the form of an annular plate positionedwithin said casing, the inner curvilinear edge of said plate beingclosely adjacent said float, said plate having a plurality of openingsof substantial area, the space between said inner curvilinear edge andsaid float being sufficiently small to retain water by capillary action,the said openings being large enough to prevent the retention of waterby capillary action,

3. In an air valve for steam radiators, in combination, a casing havingan intake port and a vent, vent-closing means comprising a float, guidemeans for said float, said guide means comprising a baiiie interposedbetween said casing and said float, said bafile being annular in formand secured to said casing, the clearance between a major portion of theinner circumference of said baffle and float being substantially uniformbut so narrow that condensate collected thereabove will not flowdownwardly through said clearance, and openings in said baflie largeenough to permit the downward flow or" condensate, the total area ofsaid baffle being suiflcient to effectively check upward surges ofwater.

4. In an air valve for steam radiators, in combination, a casing havingan intake port and a vent, vent-closing means comprising a float, guidemeans for said float, said guide means comprising a baiile interposedbetween said casing and said float, said baflie being annular in formand secured to said casing, the clearance between a major portion of theinner circumference of said battle and float being substantially uniformbut so narrow that condensate collected thereabove will not flowdownwardly through said clearance, a minor por tion of the innercircumference being cut away to form openings in said bafiie largeenough to permit the downward flow of condensate, the total area of saidbafile being sufficient to eflectively check upward surges of water.

5. In an air valve for steam radiators, in combination, a casing havingan intake port and a vent, vent-closing means comprising a float, guidemeans for said float, said guide means comprising a bafiie interposedbetween said casing and said float, said baffle being annular in formand secured to said casing, the clearance between a major portion of theinner circumference of said bafiie and float being substantially uniformbut so narrow that condensate collected thereabove will not flowdownwardly through said clearance, a minor portion of the outercircumference being cut away to form openings in said baffle largeenough to permit the downward flow or" condensate, the total area ofsaid baffle being sufficient to effectively check upward surges ofwater.

6. In an air valve for steam radiators, in combination, a casing havingan intake port and a vent, vent-closing means comprising a float, guidemeans for said float, said guide means comprising a bafile interposedbetween said casing and said float, said baffle being annular inform andsecured to said casing, the clearance between a major portion of theinner circumference of said bafiie and float being substantially uniformbut so narrow that condensate collected thereabove will not flowdownwardly through said clearance, said bafile having a plurality ofsmall cut-away areas large enough to permit the downward passage ofcondensate but small enough in proportion to the area of said bafile sothat said baflle is effective to check upward surges of water.

7. In an air valve for steam radiators, in combination, a casing havingan intake port and a vent, vent closing means comprising a float, saidcasing and float forming relatively movable members, guide means forsaid float, said guide means comprising a bafile interposed between saidrelatively movable casing and float, said baflle being annular in formand secured to one of said relatively movable members, there being aclearance between the major portion of the free circumference of saidbafiie and the other member, said clearance being substantially uniformbut so narrow that condensate collected thereabove will not flowdownwardly through said clearance, and openings in said bafile largeenough to permit the downward flow of condensate, the total area of saidbafiie being suflicient to effectively check upward surges of water.

HENRY BERGER AHLBERG.

